Segregated Witness (SegWit) is a Bitcoin protocol upgrade activated in August 2017 that restructured how transaction data is encoded and validated. It’s foundational to modern Bitcoin usage and essential for understanding current fee dynamics and layer 2 scaling. How SegWit Works Bitcoin transactions contain two main components: the transaction structure itself and the cryptographic signatures…
Every Bitcoin transaction consists of two main components: Inputs (UTXOs): Unspent Transaction Outputs from previous transactions that you’re now spending. These are references to outputs you received earlier. Think of them as specific bills from your wallet you’re handing over. Outputs: The destinations and amounts for the Bitcoin. This includes the recipient’s address and the…
Proof of Ownership is a cryptographic method to demonstrate control over a Bitcoin address’s private keys without moving funds or exposing the key itself. It’s essential for withdrawals to new addresses, OTC trades, collateral verification, and exchange account recovery. How Digital Signatures Work The mechanism relies on public-key cryptography: Challenge: A verifier (exchange, lender, service)…
PGP combines symmetric and asymmetric encryption to achieve both speed and security: Symmetric Encryption: The message itself is encrypted using a random session key with an algorithm like AES-256. This is computationally fast for large files. Asymmetric Encryption: The session key is then encrypted with the recipient’s public key using RSA or ECC. Only the…
Multisig (multisignature) is a cryptographic mechanism that requires multiple private keys to authorize a blockchain transaction. Think of it as a vault requiring two or more keys to open — no single key holder can move funds alone. How It Works A multisig wallet uses an m-of-n formula, where m is the number of signatures…
ECDSA (Elliptic Curve Digital Signature Algorithm) remains a core cryptographic standard across blockchain systems, HTTPS/TLS, and cryptocurrency wallets. Understanding how to generate and work with different ECDSA curve variants is essential for secure key management. Why ECDSA? ECDSA offers distinct advantages over RSA for many use cases: Key size efficiency: A 256-bit ECDSA key provides…
When renewing an SSL certificate, your CA will request a Certificate Signing Request (CSR). If you have the private key but need to generate a fresh CSR, OpenSSL handles this straightforwardly. Basic CSR Generation Generate a CSR from your existing private key: openssl req -new -key ssl.key -out req.pem This creates req.pem containing your CSR,…